This study aimed to estimate the genetic parameters of fertility traits in different regions,and to test the effect of genotype by environment interactions(GXE)across regions.The raw fertility data were collected from 2 064 Holstein dairy farms in 6 regions of China,including records from 2005 to 2022.A total of 1 787 590 and 2 476 422 phenotypic records were derived from the raw data for age at first calving(AFC),and calving interval(CI).Meanwhile,these phenotypes data were quality controlled and separated into different datasets for subsequent analysis.The statistical models used in this study were all incorporated in the airemlf90 module of BLUPF90.Univariate animal(and repeatability)models were used for estimating genetic parameters for these 2 traits in 6 regions,while bivariate animal(and repeatability)models were used to estimate genetic correlations between the regions,which are the indicators of G×E.The results indicated that the proposed quality control steps could filter abnormal phenotypes records.The heritabilities of AFC were relatively high and varied across regions(0.06-0.40),whereas the heritabilities of CI were low but remained similar across regions(0.02-0.04).Significant GXE effect(P＜0.05)was observed across most of the regions for both traits.In conclusion,the genetic parameters of the same fertility trait varied across the regions in China,and significant GXE effect was detected for the trait in partial regions.Therefore,it is highly recommended to consider the impacts of regional difference and GXE effect on genetic advance when breeding for fertility traits of dairy cattle in China.
关键词
奶牛/繁殖性状/遗传参数/基因型与环境互作
Key words
dairy cows/fertility traits/genetic parameters/genotype by environment interaction
维普
万方数据